Indium In 111 Oxyquinoline Solution
» Indium In 111 Oxyquinoline Solution is a sterile, nonpyrogenic, isotonic aqueous solution suitable for the radiolabeling of blood cells, especially leukocytes and platelets, containing radioactive indium (111In) in the form of a complex with 8-hydroxyquinoline, the latter being present in excess. It contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of 111In as the 8-hydroxyquinoline complex expressed as megabecquerels (millicuries) per mL at the time indicated in the labeling. It may contain sodium chloride, surfactants, and buffers. Other chemical forms of radioactivity do not exceed 10.0 percent of the total radioactivity.
Specific activity: not less than 1.85 GBq (50 millicuries) per µg of indium.
Packaging and storage Preserve in single-unit containers at a temperature between 15 and 25.
Labeling Label it to contain the following, in addition to the information specified for Labeling under Injections 1: the time and date of calibration; the amount of 111In as the 8-hydroxyquinoline complex expressed as total megabecquerels (millicuries) and concentration as megabecquerels (millicuries) per mL on the date and time of calibration; the expiration date; the statement Not for direct administration. Use only for radiolabeling of leukocytes in vitro. Administer radiolabeled cells subsequently by intravenous injection, and the statement CautionRadioactive Material. The labeling indicates that in making dosage calculations, correction is to be made for radioactive decay, and also indicates that the radioactive half-life of 111In is 67.9 hours.
Pyrogen It meets the requirements of the Pyrogen Test 151.
pH 791: between 6.5 and 7.5.
Radionuclide identification (see Radioactivity 821) Its gamma-ray spectrum is identical to that of a specimen of 111In that exhibits major photopeaks having energies of 0.171 and 0.245 MeV.
Radiochemical purity Place a suitable volume, about 100 µL, of Solution, dilute with 3 mL of 0.9 percent sodium chloride solution in a separator, and extract with 6 mL of n-octanol by vigorous shaking. Allow the phases to separate and then drain the lower, aqueous layer into a suitable stoppered counting tube. Drain the residual, organic layer into a similar counting tube. Rinse the separator with 1 mL of n-octanol, and drain this rinse into the counting tube containing the organic layer. Rinse the separator with 5 mL of 2 N hydrochloric acid, and drain this rinse into a third counting tube. Insert the stopper and measure the radioactivity in each of the three tubes in a suitable gamma counter or ionization chamber calibrated for 111In. The radiochemical purity is calculated by the formula:
(A / B)where A is the radioactivity measured in the organic layer and B is the sum of the radioactivity measured in the organic, aqueous, and acid solutions. The radioactivity of the 8-hydroxyquinoline complex is not less than 90.0% of the total radioactivity and is found in the organic layer.
Radionuclidic purity Using a suitable counting assembly (see Selection of a Counting Assembly under Radioactivity 821), determine the radioactivity of each radionuclidic impurity, in kBq per MBq (µCi per mCi) of 111In, in the Solution by use of a calibrated system as directed under Radioactivity 821.
Indium 114mThe limit of 114mIn is 3 kBq per MBq (3 µCi per mCi) of 111In. 114mIn is quantified by counting the beta emissions of ground state 114In using a beta-liquid scintillation counter with a high-energy channel set to discriminate against all counts arising from 111In.
Zinc 65The limit of 65Zn is 3 kBq per MBq (3 µCi per mCi) of 111In. The presence of 65Zn in the Solution is demonstrated by a characteristic gamma-ray spectrum with a prominent photopeak at 1.116 MeV. 65Zn decays with a radioactive half-life of 243.9 days.